Abstract: Duck manure from rice-duck eco-farming plays a crucial role in controlling Rhizoctonia solani. In this study, the antibacterial activity and effective components of duck manure extracts were analyzed for R. solani. Duck manure extracts via ethanol respectively has highest inhibition rate of 88.64% and EC50 of 26.11 mg·mL^-1 against R. solani. The extract was further separated into two parts and one part separated by ethyl acetate while the other was separated by petroleum ether. Based on the inhibition experiment against R. solani, ethly acetate extract has a rather strong effect on R. solani with 89.70% inhibition rate and 15.52 mg·mL^-1 EC50. The effect of petroleum ether extract on R. solani is relatively weak. The former was again divided into five parts in silica gel column, of which the second part significantly inhibits R. solani. During the periods of 24 and 48 hrs, the inhibition rate of the second part on R. solan is respectively 89.58% and 80.36%. GC-MS analysis suggests that the second part contains phenol sour and sulfur alcohol, which best suits further purification and identification.